Flex-Hone Applications: Cross Hole Deburring

Cross hole deburring removes metal burrs from cross-drilled holes and leaves a smooth, clean, radiused intersection. Burrs are ridges of cut, torn, jagged, or folded metal that can cause part misalignments, affect dimensional tolerances, and limit the overall efficiency of machined components. In the case of cross-drilled holes, burrs may block the flow of cooling fluids, lubricants, and gases. Often, these cross-drilled intersections are found in auto parts such as engine components and transmissions. Fortunately, the Flex-Hone® tool from Brush Research Manufacturing (BRM) provides an easy-to-use, cost-effective solution for cross hole deburring – an otherwise expensive, time-consuming operation.

What is Deburring?
Burrs and sharp edges are created when metal blanks are machined into specific shapes and sizes. Ragged edges and areas of roughness are also produced when metal parts are welded, molded, cast, trimmed, slit or sheared. Since burrs occur on seams as well as edges, deburring is used to improve surface finish so that the metal is uniformly smooth. Burrs at the intersection of holes present a special challenge since the deburring tool must smooth edges and produce a blended radius. With its unique construction, the Flex-Hone® is ideal for cross-hole deburring either during machine tool applications (on-line) or as a secondary operation (off-line).

Metal Finishing
The Flex-Hone® is self-centering and self-aligning to the bore so that rigid, elaborate setups are not required. For best results, use the deburring tool in the main bore into which the cross-holes break. Rotate and stroke the Flex-Hone a few strokes in a clockwise direction, and then remove the tool from the part. Next, reverse the spindle and rotate and stroke the Flex-Hone in a counterclockwise direction for a few more strokes. This forward and reverse rotation creates a symmetrical deburring pattern. When using the honing tool in either direction, lubricate generously with Flex-Hone® oil to keep metal cuttings and deburred metal in suspension.